Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
hanh lai » hanh lam, hanh tai, thanh lap
thuc van » thuc vat, thuc dan, thuc hanh
lai cua » dai cua, hai cua, lai chau
thuc va » thuc vat, thuc dan, thuc day
so sanh » do sanh
hieu ve » hieu va, hieu van
ve nam » he nam, va nam, le nam
ma hoi » mai hoi, xa hoi, ma hoa
7 tang » 6 tang
y tang » ky tang, 6 tang, 5 tang

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: so sanh ((y tang) or (7 tang)) ma hoi. hieu ve nam ((thuc van) OR (thuc va)) hanh lai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sanh ((y tang) OR (7 tang)) ma hoi. hieu ve nam ((thuc van) OR (thuc va)) hanh lai cua viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sanh ((y tang) or (7 tang)) ma hoi. hieu ve nam ((thuc van) OR (thuc va)) hanh lai cua viet*".